Home > Articles > Networking > Storage

21st Century Oxymorons: Jumbo Shrimp and Fibre Channel SAN

This article focuses on Fibre Channel-based SAN security. Like so many terms in the networking industry, "Storage Area Network" (SAN) boasts a bevy of definitions. Whatever form of SAN you construct must be secure enough to avoid the risk of losing or compromising critical data.
This chapter is from the book

In the last chapter, we looked at the marketecture around networked storage generally—and the Fibre Channel SAN, in particular. SANs originated as a conceptual topology for storage that provided network-based interconnections between servers and an intelligent storage infrastructure, sometimes called a "storage pool" or "storage utility."

Such a SAN was heterogeneous in nature, allowing for the any-to-any interconnection of servers with different operating systems to storage platforms from different vendors. The SAN was also intelligent, capable of recognizing the needs of applications requesting storage services and automatically provisioning applications with whatever storage services that they required. The enhanced manageability of a SAN gave it tremendous integrity as a highly available repository for mission critical data storage. And, SAN security would be more than sufficient to offset the increased risk that unavoidably accompanies increased accessibility.

Figures 3-1 and 3-2 depict the "Holy Grail" SAN as described in Enterprise Network Storage Architecture (ENSA) documentation from Compaq Computers and related writings of the late 1990s.

03fig01.jpgFigure 3-1. The Holy Grail SAN: Heterogeneous storage and server equipment with any-to-any network-based connectivity.




03fig02.gifFigure 3-2. The Holy Grail SAN: A virtual storage resource pool.

The ENSA SAN concept was truly visionary and captured the attention of storage technology producers and consumers. If it came to fruition, the SAN would establish data storage as its own infrastructure—creating a new service tier in the hierarchy of contemporary n-tier client/server computing. It could conceivably make storage infrastructure the solid, well-anchored foundation upon which networks, servers, and applications resided.

In the late 1990s, vendors and pundits alike said that the SAN was an intuitively obvious "next step" in computing. Storage was getting cheaper, with disk prices declining by as much as 50 percent per year. At the same time, however, the volume of data being stored was increasing—by more than 100 percent per year in some companies. That meant more and more storage needed to be fielded, and a lot of storage—like a lot of anything—carried with it a big price tag, both in terms of acquisition and deployment costs and labor expense.

SANS AND CAPACITY ALLOCATION EFFICIENCY

Early on, many advocates of the technology dismissed the huge acquisition and deployment costs of Fibre Channel (FC) SANs as inconsequential—especially when they were weighed against the enormous efficiencies derived from the networked storage topology. Vendors argued that an FC SAN would more than pay for itself by enabling improved capacity allocation efficiency and improved manageability.

The improved manageability of storage gathered into a FC SAN remains a myth that will be explored in greater detail later. The prospect of improved capacity allocation efficiency, however, had a strong appeal to most IT managers. To understand why, one only has to peek into any IT shop in which storage is directly attached to servers.

In virtually every IT shop, some servers have direct attached storage that tends to run out of disk space fairly often. When this happens, a "Disk Full Error" message is typically generated by the server operating system and returned to the application and/or end-user. The server administrator, who is typically responsible for performing all of the storage management and allocation in a distributed client/server setting, gets an earful from a disgruntled end-user, then spends an inordinate amount of time trying to rectify the problem by offloading files to free up space or adding more disk drives into the cabinet of the attached disk array.

Meanwhile, another server, usually located within a stone's throw of the problem server, goes merrily along about its business day in and day out without ever using more than 30 percent of its storage capacity (see Figure 3-3). The server admin looks longingly at the well-behaved server and array and wonders why there is no way to share the excess capacity on the good server's direct attached storage platform with the direct attached storage platform on the bad server, which is always running out of room.

03fig03.jpgFigure 3-3. Capacity allocation inefficiency in server attached storage.


Contained in that notion was a description of capacity allocation efficiency: the stuff, to paraphrase the Bard, that early FC SAN dreams were made of. To a one, FC SAN vendors promised that deploying a SAN would provide organizations with the ability to allocate storage capacity more efficiently across applications. Just "network" the storage into an FC SAN and any available capacity on any storage platform could be harnessed to create dynamically scalable "virtual volumes." Applications and end-users, and especially server administrators, would never see a "Disk Full Error" message again (see Figure 3-4).

03fig04.jpgFigure 3-4. Capacity allocation efficiency with virtual san-based volumes.


From this value proposition of volume virtualization derived several others. For one, vendors claimed that enabling greater capacity allocation efficiency with FC SANs would save customers money. FC SANs would actually pay for themselves by enabling older storage platforms to be kept in service for a longer period of time, deferring the need for new equipment purchases.

Additionally, since networked virtual volumes could scale readily, simply by adding more available capacity to an existing virtual volume as needed by the application, FC SANs would also eliminate the costly downtime brought about by the need to rectify disk space problems. This was, depending on the environment, another potentially huge cost savings of FC SANs—especially with estimates of downtime costs that averaged over $1 million per hour across all U.S. industries based on idle labor considerations alone. (See Figure 3-5.)

03fig05.gifFigure 3-5. Downtime costs as a function of idle labor. (Source: Performance Engineering & Measurement Strategies: Quantifying Performance Loss, META Group, Inc., Stamford, CT. October 2000. Copyright © META Group, Inc. All rights reserved. Used with permission.)


In the final analysis, the promise of capacity allocation efficiency made a compelling case for FC SANs. Unfortunately, it was not a valid one. The reason had to do with the nature of FC SANs themselves and with approaches advanced by the industry to create a virtual storage pool from devices interconnected in a FC fabric.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020